1. Field of the Invention
The invention relates to flame-resistant phthalonitrile thermoset polymers and composites that are cured with halogen-containing aromatic amine curing agents.
2. Description of the Related Art
Phthalonitrile resins made using amine curing agents are described in Keller, T. M. and Price, T. R., "Amine-Cured Bisphenol-Linked Phthalonitrile Resins", J. Macromol. Sci.-Chem., A18(6), pp. 931-937 (1982), U.S. Pat. Nos. 4,408,035 to Keller, 5,003,039 to Keller, 5,003,078 to Keller, 5,004,801 to Keller, 5,132,396 to Keller, 5,139,054 to Keller, 5,208,318 to Keller, 5,237,045 to Burchill et al, 5,292,854 to Keller and 5,350,828 to Keller et al., the disclosures of which are incorporated herein by reference.
For many practical applications, such as for structural material for ships, it is desirable that a resin-based material exhibit good flame resistance. Very good flame resistance may be obtained with phthalonitrile polymers and composites such as are described above. However, for specialized applications such as for structural material for submarines, there is always a need for material that has even better flame resistance than is currently obtainable.